Truck mounted pavement stripers are well known in the art. One such truck mounted pavement striper employs paint stored at ambient temperature in pressurized storage tanks, and conducted from the tanks to pressurized paint guns for discharge onto the road areas to be striped. Unfortunately, the drying time for such paint exceeds 10 minutes and requires protection during the drying period from smudging and tracking by vehicles using the roads. To permit the paint to dry, marking cones are set down after painting, and then later retrieved by additional workmen, carried in a separate truck following a predetermined distance behind the truck mounted pavement striper.
As a result of the deficiencies of the above system, a more advanced hot line paint system was developed. In this system, hot paint is delivered "hot" from storage for discharge "hot" at the spray guns. Upon application, the "hot" paint dries in a matter of seconds. While the need for marking cones was eliminated, a new cost factor was added--the cost to heat the paint. While several methods of heating the paint have been proposed, none have been satisfactory from a cost and/or efficiency point of view. Particularly, one such method of heating the paint provided a diesel fuel fired water heater of sufficient capacity to heat water to a given temperature (below boiling) which in turn heats the paint to a temperature of between about 180.degree.-190.degree. F. However, firing with diesel fuel requires separate storage tanks mounted in the truck for the diesel fuel at additional cost. Furthermore, the source of heat is external, i.e. the diesel fuel. Additionally, the use of water limited the heat which could be transferred to the paint. There is of course, a source of heat that is internal, i.e. part of the truck, which heat has not been used to date to heat the paint but is released to the atmosphere--the heat from the exhaust systems of the internal combustion engines of the truck and compressors if any. Tests conducted by me at the exhausts of the motor and compressor if any, revealed that temperatures of the exhaust gases exceeded 580.degree. F. While no one to date has succeeded in harnessing the exhaust gases to heat the paint, saying it could not be done, I have not only succeeded in utilizing such gases to provide the necessary heat to heat the paint, but also in providing such heat to the paint, I have been also able to provide heat in excess of the minimum necessary to achieve and maintain the paint "hot" in the system for spraying "hot" at the guns.